Al-Kāfi
Hadith 5921- عِدَّةٌ مِنْ أَصْحَابِنَا عَنْ سَهْلِ بْنِ زِيَادٍ عَنْ أَحْمَدَ بْنِ مُحَمَّدِ بْنِ أَبِي نَصْرٍ عَنْ بَعْضِ أَصْحَابِهِ عَنْ أَبِي عَبْدِ اللهِ (عَلَيْهِ السَّلام) فِي الرَّجُلِ يَبِيعُ الشَّيْءَ فَيَقُولُ الْمُشْتَرِي هُوَ بِكَذَا وَكَذَا بِأَقَلِّ مَا قَالَ الْبَائِعُ قَالَ الْقَوْلُ قَوْلُ الْبَائِعِ مَعَ يَمِينِهِ إِذَا كَانَ الشَّيْءُ قَائِماً بِعَيْنِهِ.
1. A number of our people have narrated from Sahl ibn Ziyad from Ahmad ibn Muhammad ibn abu Nasr who has said the following: “About the case of a man who sells something and the buyers says, ‘I pay so and so’ which is less than what the seller wants, abu ‘ Abd Allah (a.s.), has said, The words of the seller are accepted on oath if the merchandise still exists.”’